A plug connector is disclosed, for example, in German Patent DE 197 49 130 C1 and has two complementary, mating plug sections which contain mutually complementary electrical coupling sections. The first plug section comprises a receiving sleeve which encircles the first coupling section and which has on its inside a locking element in the form of a ring with internally projecting spring lugs. The locking element is displaceable between a locking position and an unlocking position and is pre-stressed in its locking position as a result of its spring elasticity. Held displaceably on a receiving sleeve is a sliding sleeve with which the locking element can be transferred to its unlocking position. The second plug section has a plug tube which surrounds the second coupling section. When the plug tube is inserted in the receiving sleeve, the locking element can rest in its locking position on the outside of the plug tube which appropriately has an annular groove at this point whereby the plug sections are secured on one another. This securing can be released by actuating the sliding sleeve to move the locking element into its unlocking position for which purpose an actuating section of the sliding sleeve interacts with the locking element.
In the known plug connection the sliding sleeve is held on the receiving sleeve by the fact that at an end distant from the locking element the sliding sleeve has an inwardly projecting collar which engages in an external circumferential groove which is incorporated externally in the receiving sleeve or in the first plug section. This groove in this case forms two axial stops which limit the axial displaceability of the sliding sleeve. The dimensioning of the groove is selected such that the sliding sleeve is movable within its axial stops to such an extent that the actuating section of the sliding sleeve can come completely free from the locking element. Moreover, in the known plug connection the receiving sleeve is formed integrally on the first plug section, that is the first plug section and receiving sleeve are manufactured from one piece.
The generic plug connection thus operates according to the so-called push-pull principle and is configured as self-securing for the plugging process. Another plug connection of this type is known for example from German Patent DE 299 11 792 U1 which substantially differs from the plug connection described above in that the sliding sleeve is pre-stressed in its rest position.
This is achieved in the known plug connection with the aid of an additional compression spring which is inserted in an annular cavity between the actuating section and an externally located grip section of the sliding sleeve and is supported in the axial direction on the one hand on the sliding sleeve and on the other hand on an axial front face of the first plug section. By means of this measure the handling of the plug connection, especially the first plug section, can be considerably simplified. At the same time, independent relative movements of the sliding sleeve which could result in undesirable development of noise in an environment rich in vibrations and oscillations, are suppressed. However, the known plug connection is comparatively expensive to manufacture since an additional component, namely the additional compression springs, must be incorporated in an additional production step. However, since series-produced parts are involved in the manufacture of the present invention, a significant cost disadvantage is thereby obtained.